Hey there, I just made a circuit for a 501st member's Jawa eyes, so I picked up one of the $5 single 18650 chargers to give them. I went to go charge the 3400mAh protected 18650 I got for the circuit, and it started to charge normally. Then about 5 minutes into charging, I hear a "POP" and I look and the charging LED was out, so I rushed over to unplug it and get the cell out. The cell was only a tad warm, I don't even know if it was warmer than when I put it in the charger. But the charger itself was very warm, in parts, I'd say it was hot. Also, it definitely smelled like something had burned out internally. Now, I'd regularly assume it was just a bad charger, and that it was no biggie, because they are so cheap. BUT...When I was making the circuit, the cell fit very, very tightly in the battery holder, and when I pushed it in once, the button tab-thing on the positive side of the cell slid partially off the cell. I popped it out, and saw that the metal button top was connected to the positive terminal on the cell by a ribbon-like tab. That tab also ran to the negative terminal under the shrink wrap. I couldn't reaffix the button tab, so after assessing it as just there to make a tighter fit (as on unprotected cells, there is not button head). So after some deliberation, I cut off the button head. The cell fit much better in the holder, lit up the LEDs, etc. So I thought it was all good. But then the whole charger thing happened, so I am unsure if it was just a faulty charger, or if by removing the button tab, I altered the protection circuit in the cell and caused the charger to give it too much current when charging. I tested the cell, and the PCB wasn't tripped, because it still powers the LEDs. Any idea of what went wrong, and if that cell is still safe to use?